Contraction Of Abdominal Musculature Research Articles

Analgesic Activity of Salacia korthalsiana Miq (Polipog)

Pain has always been a cause of concern to humans. People often searched for remedy from plants because of the many documented side effects of commercial medicines. This study was conducted to determine the analgesic efficacy of the root decoction of Salacia korthalsiana Miq (Polipog) found in Mondragon Northern Samar. Acetic acid-induced writhing method was used to test the analgesic activity of polipog. Writhing test is a chemical method used to induce pain of peripheral origin by injection of irritant (ex. acetic acid). The manifestations of abdominal writhing in mice were described as an arching of back, extension of hind limbs and contraction of abdominal musculature. Analgesic activity of the test compound is inferred from decrease in the frequency of writhing. From the results obtained, polipog is comparable to the commercially available drugs in terms of analgesic efficacy.

Respiratory-Induced Prostate Motion

To investigate prostate movement during deep breathing and contraction of abdominal musculature by means of dynamic MRI and analyze implications for image-guided radiotherapy of prostate cancer. A total of 43 patients and 8 healthy volunteers were examined with MRI. Images during deep respiration and during contraction of abdominal musculature (via a coughing maneuver) were obtained with dynamic two-dimensional (2D) balanced SSFP; 3 frames/s were obtained over an acquisition time of 15 s. Images were acquired in sagittal orientation to evaluate motion along both the craniocaudal (cc)-axis and anteroposterior (ap)-axis. Prostate motion was quantified semi-automatically using dedicated software tools. Respiratory induced mean cc-axis displacement of the prostate was 2.7 ± 1.9 (SD) mm (range, 0.5-10.6 mm) and mean ap-axis displacement 1.8 ± 1.0 (SD) mm (range, 0.3-10 mm). In 69% of the subjects, breathing-related prostate movements were found to be negligible (< 3 mm). The prostate displacement for abdominal contraction was significantly higher: mean cc-axis displacement was max. 8.4 ± 6.7 (SD) mm (range, 0.6-27 mm); mean anteroposterior movement was 8.3 ± 7.7 (SD) mm (range, 0.7-26 mm). Dynamic MRI is an excellent tool for noninvasive real-time imaging of prostate movement. Further investigations regarding possible applications in image-guided radiotherapy, e.g., for individualized planning and in integrated linac/MRI systems, are warranted.

Visceral Antinociceptive Effects of Spinal Clonidine Combined with Morphine, [D-Pen sup 2, D-Pen sup 5] Enkephalin, or U50,488H

Visceral pain is an important component of many clinical pain states. The perispinal administration of drug combinations rather than a single agent may reduce side effects while maximizing analgesic effectiveness. The purpose of this study was to examine the nature of interactions between an alpha 2-adrenergic agonist (clonidine) and a mu-opioid agonist (morphine), a delta-opioid agonist ([D-Pen2, D-Pen5] enkephalin [DPDPE]), or a kappa-opioid agonist (U50,488H). Colorectal distension was used to elicit a nociceptive visceromotor response (contraction of abdominal musculature) in rats. The ability of intrathecally administered clonidine alone or in combination with morphine, DPDPE, or U50,488H to alter thresholds for the production of the visceromotor response was examined. Clonidine produced dose-dependent reduction in threshold. U50,488H, at the doses tested, showed no synergistic interaction with clonidine. Spinal combinations of alpha 2-adrenergic and mu- or delta- but not kappa-opioid agonists may be beneficial in the control of visceral pain.

Contrasting actions of intrathecal U50,488H, morphine, or [D-Pen2, D-Pen5] enkephalin or intravenous U50,488H on the visceromotor response to colorectal distension in the rat.

Visceral sensations are an important component of many clinical pain states. It is apparent that intrathecal pain relief may be more effective if appropriate combinations of drugs rather than a single agent can be used. The purpose of this study was to examine the relative contribution of opioid receptor subtypes to visceral antinociception using colorectal distension as a visceral pain model. The minimum colorectal distending pressure necessary to evoke a visceromotor response (contraction of abdominal musculature) was determined before and after the administration of opioid agonists for the mu (morphine), delta ([D-Pen2, D-Pen5] enkephalin [DPDPE]), and kappa (U50,488H) opioid receptors. In addition to the three drugs administered intrathecally, U50, 488H was also administered intravenously. Morphine and DPDPE produced a reversible increase in threshold for activation of the visceromotor response (50% maximum possible effect [MPE] at intrathecal doses of 2.2 and 16.4 micrograms, respectively). The maximum intrathecal dose of U50,488H (100 micrograms) produced only a 20% MPE. Intravenous U50,488H produced a 50% MPE at a dose of 2.6 mg/kg. The results suggest that spinal mu- and delta- but not kappa-opioid receptors have a significant role in the modulation of visceral nociception induced by colorectal distension. In addition, the results indicate that activation of nonspinal kappa receptors may mediate visceral antinociception.